1. Field of the Invention
The present invention relates generally to karaoke machine technology, and specifically to a method and apparatus for using a karaoke user's vocal amplitude or voice volume to control the volume of the original lead singer's vocal which is mixed or merged with a background music track and outputted through loudspeakers to the audience.
2. Description of Related Art
Before discussing the present invention and the prior art, certain terms should be defined. As used herein: a "song" means "background music" plus "lead vocal". "Background music" is intended to mean instruments and background vocals and "lead vocal" is intended to mean the lyrics portion of the song sung by the lead singer without any instruments. An original mixed recording or "OMR" includes the lead singer original vocal and the instrumental or music part of the song. The "karaoke user" is the person who is singing, speaking, or sending sound through a microphone to the karaoke machine.
The basic and most common karaoke machines output the instrumental portion of a song with the lead vocal removed, and substitute in its place the voice of the karaoke user singing the vocal through a microphone. The karaoke user's voice and the music of the song are mixed and outputted, typically to an audience. If the karaoke user has not memorized the lyrics to the song or the placement of those lyrics in the song, there is usually a visual prompt on a screen in view of the karaoke user displaying the lyrics of the song at the appropriate times.
Karaoke, although very popular in Far Eastern countries, such as Korea and Japan, has not been popular in Western culture, particularly in the United States. Although it may not be possible to pinpoint one specific reason karaoke has not been popular with Americans, and with Westerners in general, one factor may be that they are uncomfortable with the sound of their voices. Individuals are typically self-conscious about the sound of their voice and maybe disappointed with the tone or quality of sound they produce through a karaoke machine. It is likely that if they could sound more like the actual singer, karaoke would be a greater source of entertainment. Another factor may be that they do not like having to sing the exact lyrics to a particular song even though they may like the song or like the idea of performing the song; they may rather hum the melody or make sounds that mimic or sound similar to the actual lyrics. Although the reasons for karaoke's unpopularity may be varied, it is likely that enabling the karaoke user to sound more like or exactly like the original singer would eliminate many of the barriers keeping people from using it in this country and make it more entertaining to Western audiences.
One enhancement to the basic functionality of karaoke and attempt at making it more accessible to the novice is a feature called vocal partnering. This feature enables outputting the OMR when the karaoke user's voice drops below a certain volume level. Thus, if the karaoke user is not singing at all or is singing too softly, the audience and the karaoke user will hear the OMR which is simply the lead singer's original vocal with the music and background vocals. The karaoke user may have lost his or her place in the song or momentarily forgotten the lyrics or melody. Hearing the OMR can assist the karaoke user in getting back on track in the song. Once the karaoke user starts singing louder and is more audible to the audience, the OMR is removed and the karaoke user is again heard with the music. In most cases, the OMR is not heard by the audience because the karaoke user is normally singing at an audible level. When the OMR does come on, it does so at a set volume and does not change until going off if the karaoke user starts singing again.
FIG. 1 is a block diagram of a karaoke machine which includes vocal partnering, or what is referred to as Duet Mode. The song input is comprised of two audio streams: one carrying only background music on a signal 101, and another carrying OMR on a signal 102. Signal 101 is inputted directly into a mixer 107. Signal 102 is fed into a Duet Mode enabler 103 which contains a discrete ON/OFF switch. A microphone 104 used by the karaoke participant is connected to a Duet Mode enabler 103. The strength of the signal sent through the microphone controls the ON/OFF switch. If the switch is ON, the Duet Mode enabler 103 is activated as a result of receiving a low amplitude 106 from the karaoke user via the microphone 104. The Duet Mode enabler 103 senses the volume or vocal-amplitude 106 of the karaoke user's voice through the microphone. If it senses that the vocal-amplitude 106 is below a certain level because the karaoke user is singing too softly or not at all, it will assist or boost the volume of the vocals heard by the audience by adding the OMR through the switch. The enabler 103 will switch ON by outputting the OMR at a set volume level thus making the vocals more audible to the audience. If the karaoke user starts singing louder, the Duet Mode enabler 103--constantly sensing the user's vocal-amplitude--will switch OFF and stop outputting the OMR completely.
When Duet Mode is enabled, OMR signal 102, inputted to the enabler 103 is routed to a mixer 107. Mixer 107 takes OMR signal 102 and adds it to the voice of the karaoke user 109. For example, if the song being played is by Frank Sinatra, the volume of his voice remains constant once Duet Mode has been enabled. Duet Mode is enabled when the amplitude of the karaoke user is low (i.e. when the karaoke user is singing softly or not at all). This is so that there is always some vocal being projected to the audience. As mentioned above, it can also help the uncertain karaoke user find his or her place in the song or recall the vocal melodic line in the song. When the karaoke user is singing at a normal or loud volume level, Duet Mode is disabled and signal 101 consisting only of background music is routed to mixer 107. Mixer 107 creates an audio stream 108 consisting of the karaoke user's voice 109 and the background music, which is projected to the audience through loudspeakers 110 and illustrates typical karaoke operation.
Thus, vocal partnering ensures that some vocal is always being output by the karaoke machine. The OMR is outputted when the karaoke user's volume falls below a threshold level. It should be further noted that vocal partnering through a Duet Mode enabler does not allow for adding, at varying volume levels, the OMR according to how loud the karaoke user is singing. The audience will clearly hear, for example, Frank Sinatra's voice go on or off depending on how loud the karaoke user is singing.
Although vocal partnering is helpful in assisting a karaoke user and ensuring that some vocal is always output to the audience, it does nothing to change the tone or quality of the karaoke user's own voice. As described, so long as the karaoke user is singing above a certain level, Duet Mode will be OFF and the raw user's voice will be heard.
What is needed is a karaoke machine that allows novice, unskilled, or self-conscious singers to sound more like the original lead vocalist to an audience while still allowing the unskilled singer to creatively interact with the song and audience and control the performance.